


you want a battle? (here's a war)

by youngjo



Category: ATEEZ (Band)
Genre: Alternate Universe - Demons, Blood and Violence, Demonic Possession, Enemies to Friends to Lovers, M/M, Overcoming Trauma, original NPCs - Freeform, slowburn
Language: English
Status: In-Progress
Published: 2020-05-20
Updated: 2020-05-20
Packaged: 2021-03-02 19:20:46
Rating: Mature
Warnings: Graphic Depictions Of Violence
Chapters: 1
Words: 4,328
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24281980
Author URL: https://archiveofourown.org/users/youngjo/pseuds/youngjo
Summary: The Lunar Syndicate was known for their mercilessness when it came to exorcising demons. Their legacy had traveled far and wide, even to the pits of hell. They had made a name for themselves, and everyone knew not to cross them.Park Seonghwa, one of the Lunar Syndicate's most prominent commanders, has hated demons ever since he was a child. He will stop at nothing to eradicate all of them ... even if it means using them as weapons against their own kind. When Seonghwa is forced to form a contract with a demon known as San, everything he ever thought he knew is scattered to the wind.
Relationships: Choi San/Park Seonghwa
Comments: 17
Kudos: 53





	you want a battle? (here's a war)

**Author's Note:**

> welcome to the first chapter of an au that has been brewing since january! this has been a passion project of mine but I wasn't able to sit down and begin working on it until today and, well, cranked out a whole chapter without meaning to. so, welcome to the beginning of my sanhwa demon au! 
> 
> I hope you enjoy reading it as much as I'm going to enjoy writing it!
> 
> ( tags and warnings will update with each chapter! the rating WILL go up eventually. title from bullet for my valentine! )

A crackle of lightning illuminated the horizon, revealing a towering pillar of stone. It jutted from the mountain, tremendous and alone. Glowing blue light spidered through it, giving clue to its location even without the light of the moon to guide travelers. Another streak of lightning tore through the sky, showcasing the tower in all its glory once again. A boom of thunder shook the earth and brought with it the first drops of rain, the cool droplets slickening the rocky path leading to the pillar.

Lightning flashed along the sky for a third time, revealing a form struggling up the dangerous incline. 

The shape was humanoid, clad in dark cloth. They were surely soaked to the bone and yet they continued their hike up the mountain, slipping upon the wet outcroppings and leaving a spatter of blood from scraped fingers. Their determination sang through the rock itself, the wind howling as the magic simmering within the land awoke to their sacrifice. Upon the hill, the tower began to grow brighter, eager to welcome a travel it had not seen in nearly a century. 

Until, finally, with a streak of lightning amid the clouds, they reached the base.

All at once, the rain stopped. A tumultuous atmosphere crashed over the tower, charged with energy just short of snapping. Wind howled as the tower pulled essence from the very earth it was nestled upon. The blue light grew brighter, nearly blinding, before sparks burst from the very top. Something began to float towards the ground, and the creature below collapsed upon the ground. The orb of light continued its descent until it settled next to the form curled on the rocks.

Tension dispersed from the land with a relieved sigh. 

It had begun.

————— ( < o > ) —————

“Park Seonghwa.”

He straightened up at the sound of his overseer’s voice, schooling any scrap of emotion from his features. “Yes ma’am.”

The woman, dressed in the black and green uniform of the Viridian division, met his eyes. Her eyes were an unnaturally bright green and focused on him pointedly. Flowers had been interwoven with her wavy brown hair, a tattoo in the shape of a leaf wrapping around the left side of her neck. Her name was Willow and, despite the softness of her name, was not someone you wished to cross. Willow overseen the entirety of the Viridian division, including all of its subdivisions and more; it would be wise not to piss her off.

“I would like to extend condolences to the loss of your partner.” Her gaze softened, but only a little bit. Around them, their subordinates purposefully avoided making eye contact. “I know this will be difficult for you after such a traumatic break, but you must select a new partner as soon as possible. We can’t have our best commander Linkless.”

Such was the way of war.

“Yes ma’am,” he replied again, robotic. 

Willow regarded him for a moment before she saw something that satisfied her. She turned her attention back to the rest of the room. “There have been reports of a Beta Rank lurking along the coast. I will be assigning two teams to the field to deal wi …” 

Seonghwa tuned her out, gaze focusing blankly on the opposite wall. She was right. Without a partner, he was essentially useless. No matter his attachment to his partner, good or bad, big or small, he needed one. Not just any partner though. No, the ‘partner’ they were referring to was no mere human. 

Their partners were demons, plucked from hauntings and mischief making to be offered a true purpose upon the mortal plane.

Many refused. In fact, more than eighty-percent of them did, and those demons were vanquished and sent back to a world of fire and darkness. The other twenty-percent, dubbed Linked, formed a soul-binding contract with a human. These humans became their Anchors, a being for them to feed off and provide a symbiotic relationship. The Linked gained something akin to a meal while the Anchor unlocked the true powers of their core. 

Seonghwa had never seen it like that. Demons were parasites no matter what you called them. Wretched, awful creatures who only caused misery and strife to those unlucky enough to come into contact with them. But he also recognized that he could not rid the world of the heinous creatures without first utilizing one of them. They were a shackle, a stepping stone, a weapon—many things, but he never had any qualms about using them to eradicate the rest of them. His Linked were never around long to warrant caring.

Demons did not deserve to indulge in the pleasures of human life.

“Meeting dismissed,” Willow’s voice cut in. “Don’t leave yet, Seonghwa.”

Internally, he sighed; he didn’t need another fake sympathy pep talk. He stood there in silence as the rest of his division quickly dispersed. Make no mistake, they respected both their overseer and their commander, but many of them knew when to make themselves scarce. Seonghwa wouldn’t be surprised if some of the newer recruits had their ears pressed up against the door.

“I’m not going to scold you, if that’s what you’re worried about.” She brought a hand to her hip, head tilting as she observed him.

“That’s usually how these meetings go,” he replied, tone teasing. 

Willow’s smile was small. “You wouldn’t be an excellent commander if you got away with all your mischief,” she said. “But I know you’re wondering why.”

“A little, yeah.”

She held her hand out and a ripple of light tore through the space to her left. A hand poked through, most likely the limb from her Linked, and placed a file into her open palm. The overseer took it and in turn extended it towards Seonghwa, the ripple vanishing just as quickly as it had appeared. He reached out tentatively and accepted it, noting how light the file was.

“I know you prefer to handpick your Linked but someone higher up the chain emailed this to me today. Go ahead, open it,” Willow prompted.

Seonghwa’s gaze traveled down and he flipped the file open. A stark sheet of paper glared up at him, the sheet of ink indicating it was freshly printed. He read over the information with a blank expression. Chaos-driven, no kills, just a general nuisance … it was all pretty standard for a demon file. The commander’s head tipped back up. 

“This is nearly every file we’ve ever had,” he deadpanned.

She smirked back at him. “Read the bottom, Seonghwa.”

He sighed, turning his attention back to the sheet of paper. Then his eyes went wide. “How the hell did we wrangle an Alpha Rank demon here?” 

“We didn’t.” Their eyes met, questions burning on Seonghwa’s tongue. “It surrendered willingly. It’s still partially humanoid, which is extraordinary considering how long it terrorized the southlands. Our specialists have never seen anything like it.”

“That’s all well and interesting, ma’am, but I don’t understand why this file is in my hands.” Seonghwa’s grip on it tightened, the paper wrinkling in protest.

“Alpha Rank demons with sane minds are rare, Seonghwa—you’re smart enough to know this.” Willow’s look was sharp. “As of now, I am the only person with an Alpha Rank. They could’ve given this demon to an overseer of the other divisions, but they didn’t,” she said. “They chose you.”

The gravity of that statement sank right to his bones. Seonghwa had Linked with many demons in the span of his four year career. He’d joined the Viridian division fairly young, even for the standards of the Lunar Syndicate. Seonghwa had seen and tasted battle with demons more times than he could count and would continue to do so far into the future. So, while he understood that the document in his hand foretold of a promotion on the horizon, he felt only unease. Overseers  _ always _ got first claim of Alpha Rank demons, no exceptions.

Until now, apparently.

“The demon can be found in the sub basement. It will remain there until you form a Link or until you express rejection,” she continued, “but remember that you cannot go into the field until your powers have returned.” Willow left it at that, brushing by him to exit the room. The door whirred shut behind him, leaving him standing there in silence.

He wasn’t sure what type of weight had just been put upon his shoulders but Seonghwa knew he would face it with the same resolve he had faced everything else with. This was merely another stepping stone towards his goal. Nothing more, nothing less.

If only he knew the gravity of what loomed on the horizon.

————— ( < o > ) —————

“Park Seonghwa, Viridian division commander. State your floor,” a robotic voice crackled over the speaker. 

Seonghwa sighed, placing his hand flat against the sensor before him. “Level two sub basement.”

The sensor pulsated beneath his hand, a stripe of light spinning in a circle as it processed his request. “Access granted. Please wait for arrival.”

He stepped back and let his arms hang on either side of his body. The elevator lurched, creaking in protest as the older mess of wires and metal began his descent. Seonghwa did not enjoy silence but he was grateful for the lack of tasteless music to accompany him. It took only moments for the elevator to reach his destination, sliding into place with a heavy clang, before the doors parted before him.

A long hallway of white with glass double doors at the other end revealed itself to him. He stepped onto the floor with a soft exhale and hovered there as the elevator slid shut once again. Seonghwa’s fingers ghosted over the gun holstered at his hip for reassurance before closing the distance between himself and the area that awaited him. The sensors along the hall awoke as he made his way towards the door, a hum of energy passing through the ground as the computers concealed from view whirred to life. By the time he reached the other end of the hall, his next obstacle had been formed.

Projected from two cameras positioned on either side of the doors stood a holographic version of a human lacking hair and clothes, its expression blank. The sub basements lacked guards, contrary to what many believed—at least in the traditional sense. Holographic projections were harder to possess than their human counterparts after all.

“Commander Park. A pleasure to see you as always,” an emotionless voice echoed down the hall.

_ Sure. _ “Thank you. Requesting access to walk the basement,” Seonghwa replied.

“Access granted.” The hologram stepped to the side and the doors slid open.

Pure, unfiltered demonic energy came spilling from the room. It washed over Seonghwa and filled his ears and nose, hissing against his skin angrily. The two levels of their sub basement acted like prison cells in a way, holding demons deemed worthy to be Linked until an Anchor came to browse them. The idea of it made some people uneasy. Browsing demons like they were shopping for a new pet, when many of them still looked so human, sent discomfort roiling through the stomach more often than not.

Seonghwa was not one of those people, nor was he affected by the energy clawing at his body.

He stepped into the dark room, the atmosphere around him immediately growing grim. The doors slid shut behind him and upon his arrival, sent a ripple of emotion through the underground jail. A chorus of cries, hissing, and growls rose to near deafening as the demons realized who had joined them. The second level of the basement held demons who were far out of the caliber of their kin, Alpha and Beta Ranked creatures with powers beyond comprehension, all contained by a barrier infused into the metal bars of their cells. Never had a demon broken out and the Lunar Syndicate would keep it that way.

“Lose your pretty pet already, officer?” A demon hissed as he walked by.

“Probably killed’em himself!” Another replied, and a bout of cackling laughter rippled through the basement. 

“I would burn you from the inside, you filthy human. Pick me! Let’s try it!”

“Pretty boy couldn’t handle my power!”

Seonghwa ignored all of them, stone-faced and unfazed by their jeering. They were strong now but they wouldn’t be when an Anchor actually chose them. The deal was painted as something fun for demons but it almost never was; none of them ever saw their fellow prisoners again to confirm such a thing.

His footsteps echoed amid the noises howling around him. Seonghwa already knew where he was going and he had little reason to stop otherwise. The cell he was seeking sat nestled against the far wall, away from the others crowded so closely together. Even from across the way, the glow of the bars could be seen. An angry red, bright and blinding, circulated throughout the metal to contain the creature that resided inside. It was a special cell reserved only for the strongest of demons. 

Seonghwa came to a halt outside of it, eyes raking over the expanse of the cell as he attempted to locate its resident. The demon was found in the far left corner, stretching out upon its back and staring at the ceiling. At first glance, one would think the creature was your typical human, but Seonghwa was no fool; he saw right through the concealing mirage. The side facing him was human-like, with a few patches of blackness shaped like feathers here or there, while its right side had completely undergone the change into its true form. A black feathered wing sat crooked and bent wrong up against the bars, exposed right side covered in feathers. Shiny black talons poked from the demon’s fingers while its feet had formed into bird-like talons, deadly and large. Depthless black eyes whipped his direction as he arrived, revealing a half-formed white beak protruding from the corner of the creature’s mouth. A swathe of hair on the demon’s head was stark white against the rest of the blackness and appeared to be the only indicator of what color it had been in the past. The cage contained most of its power so while he knew the demon was of Alpha class, its presence truly felt like nothing.

“Hello, demon.” 

He had only just finished speaking before the creature was up against the bars, teeth bared to reveal terrifying fangs as it growled. 

Seonghwa was unimpressed. “Have you lost your sanity already? Pathetic.”

The demon hissed once again but still Seonghwa did not react. Realizing that the human before it was unafraid, its defense slowly lowered.  _ Seonghwa _ was the threat; it realized this.

“Do not bare your teeth at me again, demon,” he began, “or you will realize much quicker how unkind I am.”

“Bold words for someone standing outside of a cage,” it snarled.

A brow rose. It appeared this demon had a little more fight than he was told. Seonghwa briefly pondered over whether it had truly surrendered willingly. His arm shot through the slotted bars and he clasped his hand around the demon’s throat, yanking it up against the barrier preventing it from escaping. Seonghwa met its surprised look with hard eyes.

“Listen here, demon. The only reason you’re still alive is because some Specialist deemed your worthless life to hold value. You are here for one purpose and if you do not fulfill that purpose, you will be cast down to a world of fire and endless torture.” The demon’s eyes went wide, mouth hanging open in shock. “This is an advanced facility created for the sole purpose of a war with your kind. You can either aid us in eradicating them or you can become another nameless tick on my list of vanquished demons.” He let go, withdrawing his hand from the cage. “Whether you live or die down here makes no difference to me.”  _ But perhaps your human side would like a chance at retribution.  _ Seonghwa had never cared for that line of the pitch.

“Damn, you’re even scarier than ol’ Tortimer,” the demon grumbled, rubbing its taloned hand over its neck. All of its fight had drained, its one wing drooping just like its posture. “Do I get to leave this shitty cage or am I stuck down here forever? It’s been dreadfully boring.”

“You will be provided with room and board, given you don’t cause trouble.” Seonghwa produced a knife from a sheath at his other hip. “We are not alive based on hesitation.” 

The demon stared at him in open contempt. Seonghwa had felt bad for the abhorrent creatures once, back before he witnessed his own mentor succumb willingly to darkness. But he knew now. Demons were only good at bringing misfortune and destroying the happy lives of humans. In his eyes, you were smart if you never trusted a demon. Were it his choice, they would’ve returned to the old salt and brimstone method of exorcism years ago—but it wasn’t, and that’s why he had a knife hovering centimeters from a web of thin scars already decorating his palm.

“Great. Stepping from one cage to another.” The demon hissed but Seonghwa could tell it wasn’t directed at him. If anything, it was most likely upset at its own foolishness that landed it here in the first place. “Eh, to hell with it. Grass looks greener on the other side or whatever.” It smiled, unnatural and terrifying. “Hope you’re ready, pretty boy; I’m not a very good listener.”

“You’ll learn to be.”  _ Whether you like it or not. _ “I am going to remove your hand from the cage. Try anything and I will cut it off. Don’t test my already thin patience.” He got a shrug in response. So, Seonghwa reached between the bars with his free hand and snatched the demon’s humanoid wrist. It was pulled from the barrier with no resistance and then locked into place, forcing the demon’s palm to face the ceiling. “It will be better for you not to lie here, demon. State your name.”

The creature hissed in anger. “I was not aware I needed to give away my name for this!”

Seonghwa’s smirk was subtle. The only joy that came from Linking with demons came in the form of stealing their names just like they stole the souls of humans. Names were sacred in the demon world. If a human knew your name, you were well and truly fucked. It was the highest of bindings in the demon world and was only ever done with creatures you well and truly trusted.

The Lunar Syndicate did not care for such tradition.

“You will give it, or you will die down here. Your choice,” he replied, voice devoid of emotion.

“Curse you damn humans.” A spark of fire curled along the demon’s palm and Seonghwa’s brows rose, taking note of what kind of abilities he was about to gain access to. The demon heeded his earlier words however and it was not directed towards him; the flames fizzled out just as quickly as it came. “My name is Salpsan.” 

Something pulled at the back of his mind, indicating familiarity, but it was gone just as quickly. Instead, Seonghwa nodded. He raised his knife and drew the silver blade across his palm. The scent of blood made the demon involuntarily snarl, lips quivering as the animalistic urge to consume surged through it. A chorus of angry hissing and growling followed, the other demons locked within the sub basement reacting to the smell of fresh blood in close proximity. Seonghwa raised his hand, blood dripping onto the floor.

“I, Park Seonghwa, pledge myself as human Anchor for the demon known as Salpsan. With this bloodpact, I Link our souls and together we forge this contract,” Seonghwa recited. The moment he finished speaking, he slashed the knife along Salpsan’s palm. A tar-like substance, the demon’s blood, oozed from the gash. Seonghwa pressed their palms together and braced himself for the inevitable pain about to flow through him.

It came with a vengeance, hot and heavy. The fire qualities of the demon burned through him just as a wildfire tears through a forest. He didn’t scream but  _ fuck _ did he want to. Power hummed to life deep within him, flooding into his core and continuing to do so until it felt like his chest was about to burst open. Seonghwa had never Linked with an Alpha Rank demon before and not a single soul had warned him it would hurt this bad. By the time their contract was sealed, Seonghwa’s knees gave out.

He collapsed onto the hard floor with a guttural moan. Every inch of his body hurt, humming with newfound energy that threatened to spill forth at any moment. His very cells felt like they had been seared with heat, his heart hammering in his chest. Salpsan’s powers were incredible, more than Seonghwa had imagined they would be, and it would take him at least a day to fully access how to contain them within himself. His right shoulder burned especially hot, indicating that their binding tattoo had appeared there. Panting, his eyes raised to seek out Salpsan.

The demon was sitting in the center of the cage, its head thrown back in a silent scream. A series of glowing red runes had appeared along Salpsan’s skin, pulsating with the same intensity as the energy within Seonghwa’s own body. The bird traits had all but vanished, leaving a creature that one could mistake for a human without knowing its true nature easily. Salpsan fell forward onto its hands as the runes began to move along his skin. They were sucked to his right shoulder, gathering into a burning mass until they all arrived. A burst of light popped from the area, Seonghwa squinting slightly as the outline of a feather settled into place there. 

“Fuck, let’s not do that again,” the demon groaned, collapsing onto the ground.  _ This is gonna fucking suck, _ Salpsan thought right after and Seonghwa smirked. He’d have to teach the demon how to control his thoughts through their link, first and foremost.

He gripped the bars, pulling himself back onto his feet. Seonghwa pulled a tissue from his uniform pocket and cleaned the blood from the knife before shoving it back into its sheath. “With that, we are now Linked. As of now, you are bound to the commander of the Viridian division, granting you status. Should you complete your training, you will gain further freedom.”

_ Great, look what you got yourself into now, San. Tortimer’s gonna come back just to kill me twice. _ The demon sighed.  _ Of course I get stuck with some big hotshot. Maybe I should’ve just asked him to kill my ass. _

“Is your name Salpsan or San? And how should I refer to you?” Seonghwa questioned, enjoying the taste of surprise along his tongue.

“Great, you’re in my thoughts now?” Salpsan rose, grimacing.

“It comes with the Link, something you will learn in the coming days. I am used to it now.” Seonghwa tapped three times on one of the bars. A small panel opened in the floor, projecting a keypad at waist level. He tapped the code for the door of the demon’s cell and hit enter. The cage rumbled before the four bars between them slowly retreated into the expanse of the floor, giving Salpsan the freedom to exit. 

It eyed the space between them, both Seonghwa’s face and the door beyond. “What’s to stop me from running away right now? Or from killing you?”

Seonghwa laughed drily. “You’re welcome to try, but I promise it won’t end well for you.” 

Salpsan appeared to take his word for it. The demon took a tentative step towards the cage opening, placing a bare foot upon the cool stone curiously. “My name is Salpsan; I didn’t lie to you, but I would prefer San. Only my dad calls me Salpsan.” He grinned. “I may look funny but I’m a guy, so I would also prefer if you didn’t refer to me as ‘demon’ from here.”

“Alright. Now follow; we have much to do before the sun dips below the horizon.” Seonghwa turned his back upon the demon and began to walk. He only got two steps before he felt a rush of energy behind him. The commander sighed as bright green flame enveloped his body, simmering along a barrier just above his skin. 

San’s laughter fizzled out once the flame dispersed, revealing Seonghwa completely untouched.

He turned, expression dark and deadly. “For an Alpha Rank demon, you lack the wits of one.” His eyes glowed bright green and then San collapsed onto the floor, writhing against it with a tangled mess of angry hisses and disgruntled growls. Seonghwa kept him there for nearly thirty seconds before he released his grip, crossing to the collapsed demon in two steps. He dropped to his knee and tangled his fingers into San’s hair, pulling him upright so their eyes met.

“This contract is not filed in your favor, San. I have killed many of my Links for insubordination and I am not afraid to do it again.” The demon hissed at him as he let go of his hair, instead hooking a hand beneath his arm and forcing him onto his feet. “The next time you lash out at me will be your last.” Seonghwa let him go and turned his back on the humiliated demon once more, his eyes still glowing and hot. Despite the very real danger to his life, his veins felt alive with energy.

He smirked, tuning out the noises of the other demons waiting for their chance to sign their names away as he walked back to the double doors. His life in the Lunar Syndicate was about to change drastically. 

Seonghwa just didn’t know if that would be a good thing or not yet.

**Author's Note:**

> find me on twt [@moonswallowed](https://twitter.com/moonswallowed) (18+ only) for fic spoilers and pics of youngjo!
> 
> thank you for reading!!


End file.
